The average size of each population unit (including single wolves, pairs, and packs) observed was 4.2, although packs of as many as 13 wolves were sighted. Radiotagged wolves spent most of their daylight hours resting during winter, and when traveling, hunting or feeding during the day, tended to do so before 11:00 a.m. and after 3:00 p.m. Considerable variation was discovered in the movement patterns of individual wolves, with straight line distances between consecutive daily locations ranging from 0.0 to 12.8 miles, and between weekly locations, 0.0 to 49.0 miles. A pack of five wolves used a range about 43 square miles in extent, whereas lone wolves covered areas many times this size. One animal in an apparent dispersal was tracked a straight line distance of 129 miles between extreme points. A reddish male wolf was the leader of the pack of five and led two observed chases after alien wolves in the pack's territory. This animal was also most active during scent marking by the pack. Lone wolves were apparently indifferent to other wolves, and thus exclusive areas, or territories, were not observed among lone wolves. Hunts involving a total of seven deer were observed and described, and two successful attacks on deer were interpreted from tracks in the snow. Wolves generally consumed all the flesh and much of the hair and bones from kills, except during February and March 1969 when extreme snow conditions increased the vulnerability of deer to an unusual degree. At that time kills were found that were partly or totally uneaten. The kill rate by radiotagged wolves and associates during the winter of 1968-69, based on 468 wolf-days of data, varied from one deer per 6.3 days to one per 37.5 days per wolf, with the average being one deer per 10 to 13 days. The rate was much lower per wolf for members of the pack of five than for lone wolves, and much lower before February 1, 1969, than after. The average rate of kill during more usual winters was estimated to be about one deer per 18 days. This is a consumption rate of about 5.6 pounds of deer per wolf per day. Indirect evidence based on comparisons of pack-size distributions for different periods indicates that the wolf density in the study area may have increased since 1953, but that it has remained the same from 1967 to 1969. On the basis of data presented in this paper, the following hypothesis about the organization of the wolf population studied is proposed: The wolf population consists basically of groups of breeding packs defending territories of limited size, with lone wolves and other nonbreeding population units, tolerant of each other, shifting about in much larger nonexclusive areas among these territories. ACKNOWLEDGMENTS